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United States Patent | 5,598,437 |
Gourse | January 28, 1997 |
A multichannel frequency phase variable signal source is described having particular application in the simulation of an emitter environment for testing interferometer receivers. An improved direct digital frequency synthesizer produces phase information for initiating the operation of a related frequency synthesizer at a different phase point from those of the remainder of the synthesizers forming the multi channel source. An improved direct digital frequency synthesizer is described for varying this phase information.
Inventors: | Gourse; Stanley J. (Highland, MD) |
Assignee: | Litton Systems, Inc. (Woodland Hills, CA) |
Appl. No.: | 092610 |
Filed: | July 16, 1993 |
Current U.S. Class: | 375/308; 327/106; 375/279; 708/271; 708/272; 708/276 |
Intern'l Class: | H04L 027/18 |
Field of Search: | 375/67.52 364/718,721 328/14,63,155 332/16 R,117,144 307/262,269 327/106 |
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